Пример #1
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            switch (instruction.Argument1)
            {
            case (int)Register.AX:
            case (int)Register.CX:
            case (int)Register.DX:
            case (int)Register.BX:
            case (int)Register.SP:
            case (int)Register.BP:
            case (int)Register.SI:
            case (int)Register.DI:
            case (int)Register.IP:
            case (int)Register.CS:
            case (int)Register.DS:
            case (int)Register.ES:
            case (int)Register.SS:
                //case unchecked((int)Register.FLAGS):
                cpu.SetRegister((Register)instruction.Argument1, cpu.Pop());
                break;

            case unchecked ((int)Register.FLAGS):
                cpu.SetRegister((Register)instruction.Argument1, cpu.Pop());
                break;

            case OpCodeManager.ARG_DEREFERENCE:
            case OpCodeManager.ARG_MEMORY:
                var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
                cpu.WriteU16(address, cpu.Pop());
                break;

            default:
                throw new ArgumentOutOfRangeException();
            }
        }
Пример #2
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            var value = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument2, instruction.Argument2Value, instruction.Argument2Displacement);

            switch (instruction.Argument1)
            {
            case (int)Register.AX:
            case (int)Register.CX:
            case (int)Register.DX:
            case (int)Register.BX:
            case (int)Register.SP:
            case (int)Register.BP:
            case (int)Register.SI:
            case (int)Register.DI:
            case (int)Register.IP:
            case (int)Register.CS:
            case (int)Register.DS:
            case (int)Register.ES:
            case (int)Register.SS:
                cpu.SetRegister((Register)instruction.Argument1, value);
                break;

            case OpCodeManager.ARG_BYTE_REGISTER:
                cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)value);
                break;

            case OpCodeManager.ARG_DEREFERENCE:
            case OpCodeManager.ARG_MEMORY:
                var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    cpu.WriteU8(address, (byte)value);
                }
                else
                {
                    cpu.WriteU16(address, value);
                }
                break;

            default:
                throw new NotImplementedException();
            }
        }
Пример #3
0
        private ushort ProcessExchangeSecond(Cpu8086 cpu, OpCodeManager.Instruction instruction, ushort value)
        {
            ushort tmp;

            switch (instruction.Argument2)
            {
            case (int)Register.AX:
            case (int)Register.CX:
            case (int)Register.DX:
            case (int)Register.BX:
            case (int)Register.SP:
            case (int)Register.BP:
            case (int)Register.SI:
            case (int)Register.DI:
            case (int)Register.IP:
            case (int)Register.CS:
            case (int)Register.DS:
            case (int)Register.ES:
            case (int)Register.SS:
                tmp = cpu.GetRegister((Register)instruction.Argument2);
                cpu.SetRegister((Register)instruction.Argument2, (byte)value);
                break;

            case OpCodeManager.ARG_BYTE_REGISTER:
                tmp = cpu.GetRegisterU8((Register)instruction.Argument2Value);
                cpu.SetRegisterU8((Register)instruction.Argument2Value, (byte)value);
                break;

            case OpCodeManager.ARG_DEREFERENCE:
            case OpCodeManager.ARG_MEMORY:
                var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument2, instruction.Argument2Value, instruction.Argument2Displacement);
                tmp = cpu.ReadU16(address);
                cpu.WriteU16(address, value);
                break;

            default:
                throw new NotImplementedException();
            }
            return(tmp);
        }
Пример #4
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            var segment = Register.DS;

            if (instruction.SegmentPrefix != Register.Invalid)
            {
                segment = instruction.SegmentPrefix;
            }

            var  sourceAddress = InstructionHelper.SegmentToAddress(cpu.GetRegister(segment), cpu.GetRegister(Register.SI));
            var  destAddress   = InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI));
            byte size;

            if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
            {
                var value = cpu.ReadU8(sourceAddress);
                cpu.WriteU8(destAddress, value);
                size = 1;
            }
            else
            {
                var value = cpu.ReadU16(sourceAddress);
                cpu.WriteU16(destAddress, value);
                size = 2;
            }

            if (!cpu.GetFlags().Has(FlagsRegister.Direction))
            {
                cpu.IncRegister(Register.DI, size);
                cpu.IncRegister(Register.SI, size);
            }
            else
            {
                cpu.DecRegister(Register.DI, size);
                cpu.DecRegister(Register.SI, size);
            }
        }
Пример #5
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            byte size;

            if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
            {
                cpu.WriteU8(InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI)), (byte)(cpu.GetRegister(Register.AX) & 0xFF));
                size = 1;
            }
            else
            {
                cpu.WriteU16(InstructionHelper.SegmentToAddress(cpu.GetRegister(Register.ES), cpu.GetRegister(Register.DI)), cpu.GetRegister(Register.AX));
                size = 2;
            }

            if (!cpu.GetFlags().Has(FlagsRegister.Direction))
            {
                cpu.IncRegister(Register.DI, size);
            }
            else
            {
                cpu.DecRegister(Register.DI, size);
            }
        }
Пример #6
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            var value = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
            int result;

            switch (instruction.Type)
            {
            case OpCodeManager.InstructionType.Decrement:
                result = value - 1;
                InstructionHelper.CalculateDecFlags(cpu, instruction.Flag, value, 1, result);
                break;

            case OpCodeManager.InstructionType.Increment:
                result = value + 1;
                InstructionHelper.CalculateIncFlags(cpu, instruction.Flag, value, 1, result);
                break;

            case OpCodeManager.InstructionType.Negate:
                result = ~value + 1;
                InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, 0, value, result);
                break;

            case OpCodeManager.InstructionType.Not:
                result = ~value;
                break;

            default:
                throw new OutOfMemoryException();
            }

            switch (instruction.Argument1)
            {
            case (int)Register.AX:
            case (int)Register.CX:
            case (int)Register.DX:
            case (int)Register.BX:
            case (int)Register.SP:
            case (int)Register.BP:
            case (int)Register.SI:
            case (int)Register.DI:
            case (int)Register.IP:
            case (int)Register.CS:
            case (int)Register.DS:
            case (int)Register.ES:
            case (int)Register.SS:
                cpu.SetRegister((Register)instruction.Argument1, (ushort)result);
                break;

            case OpCodeManager.ARG_BYTE_REGISTER:
                cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)result);
                break;

            case OpCodeManager.ARG_DEREFERENCE:
            case OpCodeManager.ARG_MEMORY:
                var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    cpu.WriteU8(address, (byte)result);
                }
                else
                {
                    cpu.WriteU16(address, (ushort)result);
                }
                break;

            default:
                throw new NotImplementedException();
            }
        }
Пример #7
0
        public void Dispatch(Cpu8086 cpu, OpCodeManager.Instruction instruction)
        {
            var value1 = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
            var value2 = InstructionHelper.GetInstructionValue(cpu, instruction.Flag, instruction.SegmentPrefix, instruction.Argument2, instruction.Argument2Value, instruction.Argument2Displacement);

            if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
            {
                value1 &= 0xFF;
                value2 &= 0xFF;
            }

            int  result;
            bool carry;

            switch (instruction.Type)
            {
            case OpCodeManager.InstructionType.Adc:
                result = value1 + value2 + (cpu.GetFlags().Has(FlagsRegister.Carry) ? 1 : 0);
                InstructionHelper.CalculateAddFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Add:
                result = value1 + value2;
                InstructionHelper.CalculateAddFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.And:
            case OpCodeManager.InstructionType.Test:
                result = value1 & value2;
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Compare:
            case OpCodeManager.InstructionType.Subtract:
                result = value1 - value2;
                InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Or:
                result = value1 | value2;
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Rcl:
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    const int mask  = 0x1FF;
                    var       shift = (value2 & 0x1F) % 9;

                    result = (byte)value1;
                    if (cpu.Flags.Has(FlagsRegister.Carry))
                    {
                        result |= 0x100;
                    }
                    result = (byte)(result << shift) | (byte)(result >> (-shift & mask));
                    if ((result & 0x100) != 0)
                    {
                        cpu.Flags |= FlagsRegister.Carry;
                    }
                    else
                    {
                        cpu.Flags &= ~FlagsRegister.Carry;
                    }

                    if (value2 == 1)
                    {
                        if (((result & 0x100) != 0) ^ ((result & 0x80) != 0))
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                        else
                        {
                            cpu.Flags &= ~FlagsRegister.Overflow;
                        }
                    }
                }
                else
                {
                    const int mask  = 0x1FFFF;
                    var       shift = (value2 & 0x1F) % 17;

                    result = value1;
                    if (cpu.Flags.Has(FlagsRegister.Carry))
                    {
                        result |= 0x10000;
                    }
                    result = (ushort)(result << shift) | (ushort)(result >> (-shift & mask));
                    if ((result & 0x10000) != 0)
                    {
                        cpu.Flags |= FlagsRegister.Carry;
                    }
                    else
                    {
                        cpu.Flags &= ~FlagsRegister.Carry;
                    }

                    if (value2 == 1)
                    {
                        if (((result & 0x10000) != 0) ^ ((result & 0x8000) != 0))
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                        else
                        {
                            cpu.Flags &= ~FlagsRegister.Overflow;
                        }
                    }
                }
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Rcr:
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    const int mask  = 0x1FF;
                    var       shift = (value2 & 0x1F) % 9;

                    result = (byte)value1;
                    if (cpu.Flags.Has(FlagsRegister.Carry))
                    {
                        result |= 0x100;
                    }

                    if ((result & 0x1) != 0)
                    {
                        cpu.Flags |= FlagsRegister.Carry;
                    }
                    else
                    {
                        cpu.Flags &= ~FlagsRegister.Carry;
                    }

                    result = (byte)(result >> shift) | (byte)(result << (-shift & mask));

                    if (value2 == 1)
                    {
                        if (((result & 0x80) != 0) ^ ((result & 0x40) != 0))
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                        else
                        {
                            cpu.Flags &= ~FlagsRegister.Overflow;
                        }
                    }
                }
                else
                {
                    const int mask  = 0x1FFFF;
                    var       shift = (value2 & 0x1F) % 17;

                    result = value1;
                    if (cpu.Flags.Has(FlagsRegister.Carry))
                    {
                        result |= 0x10000;
                    }

                    if ((result & 0x1) != 0)
                    {
                        cpu.Flags |= FlagsRegister.Carry;
                    }
                    else
                    {
                        cpu.Flags &= ~FlagsRegister.Carry;
                    }

                    result = (ushort)(result >> shift) | (ushort)(result << (-shift & mask));

                    if (value2 == 1)
                    {
                        if (((result & 0x8000) != 0) ^ ((result & 0x4000) != 0))
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                        else
                        {
                            cpu.Flags &= ~FlagsRegister.Overflow;
                        }
                    }
                }
                //cpu.CalculateBitwiseFlags(instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Rol:
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    const int mask  = 0xFF;
                    var       shift = value2 & mask;
                    result = (byte)(value1 << shift) | (byte)(value1 >> (-shift & mask));
                }
                else
                {
                    const int mask  = 0xFFFF;
                    var       shift = value2 & mask;
                    result = (ushort)(value1 << shift) | (ushort)(value1 >> (-shift & mask));
                }
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Ror:
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    const int mask  = 0xFF;
                    var       shift = value2 & mask;
                    result = (byte)(value1 >> shift) | (byte)(value1 << (-shift & mask));
                }
                else
                {
                    const int mask  = 0xFFFF;
                    var       shift = value2 & mask;
                    result = (ushort)(value1 >> shift) | (ushort)(value1 << (-shift & mask));
                }
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Sbb:
                result = value1 - (value2 + (cpu.GetFlags().Has(FlagsRegister.Carry) ? 1 : 0));
                InstructionHelper.CalculateSubFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            case OpCodeManager.InstructionType.Shl:
                bool overflow;
                result = value1 << (value2 & 0x1F);
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result);
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    carry    = (result & 0x100) != 0;
                    overflow = (result & 0x80) != 0;
                }
                else
                {
                    carry    = (result & 0x10000) != 0;
                    overflow = (result & 0x8000) != 0;
                }
                if (carry)
                {
                    cpu.Flags |= FlagsRegister.Carry;
                }
                if ((value2 & 0x1F) == 1 && overflow ^ carry)
                {
                    cpu.Flags |= FlagsRegister.Overflow;
                }
                break;

            case OpCodeManager.InstructionType.Sar:
                if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                {
                    carry  = (((sbyte)value1 >> ((value2 & 0x1F) - 1)) & 1) != 0;
                    result = (sbyte)value1 >> (value2 & 0x1F);
                }
                else
                {
                    carry  = (((short)value1 >> ((value2 & 0x1F) - 1)) & 1) != 0;
                    result = (short)value1 >> (value2 & 0x1F);
                }
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result);
                if (carry)
                {
                    cpu.Flags |= FlagsRegister.Carry;
                }
                break;

            case OpCodeManager.InstructionType.Shr:
                carry  = ((value1 >> ((value2 & 0x1F) - 1)) & 1) != 0;
                result = value1 >> (value2 & 0x1F);
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, (ushort)(value2 & 0x1F), result);
                if (carry)
                {
                    cpu.Flags |= FlagsRegister.Carry;
                }
                if ((value2 & 0x1F) == 1)
                {
                    if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                    {
                        if ((value1 & 0x80) != 0)
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                    }
                    else
                    {
                        if ((value1 & 0x8000) != 0)
                        {
                            cpu.Flags |= FlagsRegister.Overflow;
                        }
                    }
                }
                break;

            case OpCodeManager.InstructionType.Xor:
                result = value1 ^ value2;
                InstructionHelper.CalculateBitwiseFlags(cpu, instruction.Flag, value1, value2, result);
                break;

            default:
                throw new NotImplementedException();
            }

            var truncResult = instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8) ? (byte)result : (ushort)result;

            if (instruction.Type != OpCodeManager.InstructionType.Compare && instruction.Type != OpCodeManager.InstructionType.Test)
            {
                switch (instruction.Argument1)
                {
                case (int)Register.AX:
                case (int)Register.CX:
                case (int)Register.DX:
                case (int)Register.BX:
                case (int)Register.SP:
                case (int)Register.BP:
                case (int)Register.SI:
                case (int)Register.DI:
                case (int)Register.IP:
                case (int)Register.CS:
                case (int)Register.DS:
                case (int)Register.ES:
                case (int)Register.SS:
                    cpu.SetRegister((Register)instruction.Argument1, truncResult);
                    break;

                case OpCodeManager.ARG_BYTE_REGISTER:
                    cpu.SetRegisterU8((Register)instruction.Argument1Value, (byte)truncResult);
                    break;

                case OpCodeManager.ARG_DEREFERENCE:
                case OpCodeManager.ARG_MEMORY:
                    var address = InstructionHelper.GetInstructionRealAddress(cpu, instruction.SegmentPrefix, instruction.Argument1, instruction.Argument1Value, instruction.Argument1Displacement);
                    if (instruction.Flag.Has(OpCodeManager.OpCodeFlag.Size8))
                    {
                        cpu.WriteU8(address, (byte)truncResult);
                    }
                    else
                    {
                        cpu.WriteU16(address, truncResult);
                    }
                    break;

                default:
                    throw new NotImplementedException();
                }
            }
        }